US 12,085,693 B2
Optical lens group
Litong Song, Ningbo (CN); and Lin Huang, Ningbo (CN)
Assigned to ZHEJIANG SUNNY OPTICAL CO., LTD, Ningbo (CN)
Filed by Zhejiang Sunny Optical Co., Ltd, Ningbo (CN)
Filed on Sep. 1, 2020, as Appl. No. 17/009,688.
Application 17/009,688 is a continuation of application No. PCT/CN2019/095612, filed on Jul. 11, 2019.
Claims priority of application No. 201811179873.8 (CN), filed on Oct. 10, 2018.
Prior Publication US 2020/0400923 A1, Dec. 24, 2020
Int. Cl. G02B 13/18 (2006.01); G02B 9/62 (2006.01); G02B 13/00 (2006.01); G02B 27/00 (2006.01)
CPC G02B 13/0045 (2013.01) [G02B 9/62 (2013.01); G02B 27/0025 (2013.01)] 16 Claims
OG exemplary drawing
 
1. An optical lens group, comprising: a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, which are sequentially arranged from an object side to an image side of the optical lens group along an optical axis,
wherein,
the first lens has negative refractive power;
the second lens has refractive power and a concave image-side surface;
the third lens has refractive power and a convex image-side surface;
the fourth lens has positive refractive power, and a convex object-side surface;
the fifth lens has negative refractive power; and
the sixth lens has refractive power,
wherein the third lens is made of glass, and
wherein 1.5<CT3/CT4<2.5, where CT3 is a center thickness of the third lens along the optical axis, and CT4 is a center thickness of the fourth lens along the optical axis;
wherein 0.6<ET6/CT6<1,
where ET6 is an edge thickness of the sixth lens in a direction parallel to the optical axis, and CT6 is a center thickness of the sixth lens along the optical axis; and
wherein an image-side surface of the sixth lens has an inflection point and a critical point, and 0.5<YC62/DT62<1,
where YC62 is a vertical distance from the critical point of the image-side surface of the sixth lens to the optical axis, and DT62 is an effective half-aperture of the image-side surface of the sixth lens, wherein the critical point of the image-side surface of the sixth lens refers to a point, except for an intersection point with the optical axis, on the image-side surface of the sixth lens that is tangent to a tangent plane perpendicular to the optical axis.